Bis-(o:o-diethyl-dithiophosphoryl) 1:4-butylene-dimethyl ether



United States Patent BIS-(0:O-DIETHYL-DITHIOPHOSPHORYL) 1:4- BUTYLENE-DIMETHYL ETHER Otto Scherer, Helmut Hahn, and HeinzFrensch, Frankfurt am Main, Ludwig Friedrich Emmel, Bergen-Enkheim, near Frankfurt am Main, and Wilhelm Staudermann, Frankfurt am Main, Germany, assignors to Farhwerke Hoechst Aktiengesellschaft vormals Meister Lucius & Bruning, Frankfurt am Main, Germany, a corporation of Germany No Drawing. Application April 2, 1957 Serial No. 650,079

1 Claim. (Cl. 260-461) It is known to use neutral phosphoric acid esters and sulphur derivatives thereof for the destruction of pests and spider mites. However, notwithstanding the excellent properties that these compounds possesss in some respects, they have no or only an inadequate action on the eggs of the pests. Such action is desirable, especially in the case of pests that propagate rapidly and continually and of which the generations partly overlap, so that adult animals exist simultaneously with their eggs. It has not been possible hitherto simultaneously to destroy, for example, spider mites (red spiders, tetranychidae) and their eggs.

The present invention provides as pesticides neutral bis-phosphoric acid esters which correspond to the general formula O-Ra in which R -R each represent an alkyl or alkenyl group containing 1-4 carbon atoms, X represents oxygen or sulphur, and Y represents oxygen, sulphur or -O(CH ),,O (in which n is a whole number from 1 to The invention also provides a process for the manufacture of neutral bis-phosphoric acid esters of the above formula, wherein an appropriate dialkyl or dialk-enyl phosphoric acid or thio-phosphoric acid or a metal salt or halide of such acid is reacted with an ether or thioether of the formula ZCH --YCH Z, in which the Zs represent halogen atoms or hydroxyl groups, and Y has the meaning given above, for example, symmetrical dichlorodimethyl ether, symmetrical dichlorodimethyl thioether or 1,4-butylene glycolbis-(chloromethyl ether).

The compounds of this invention possess a combined insecticidal, acaricidal and ovicidal action. They therefore have a wide range of application and can be used against both sucking and biting insects and also against spider mites (Arachnoidea) and their eggs, so that the need for repeated applications is avoided.

In contradistinction to known ovicides, the compounds of this invention have the special advantage that they kill the embryos of all ages. After their penetration into the egg they exhibit an after-eifect which, even if the embryo further develops for a short time, finally causes its death.

The field of application of the compounds of this invention is not restricted to plant protection but extends to other kinds of pest control, such as the control of domestic pests, warehouse pests and pests injurious to health.

The active substances of this invention can be applied in the dry or wet state, for example, as spraying, dusting or strewing preparations or solutions, if desired,

in combination, for example, with other insecticides, acaricides, ovicides, fungicides or synergists.

The following examples illustrate the invention.

EXAMPLE 1 Bis-(O:O-dimethyl-dithiophosphoryl)-dimethyl ether 46 grams of dichlorodimethyl ether are introduced dropwise in the course of 15 minutes, while heating, into 165 grams of potassium dimethyl dithiophosphate suspended in 200 cc. of methylene chloride. After heating the mixture for 2 hours at 45 C., the precipitated salt is separated and the solution is evaporated. grams of his (0:0 dimethyldithiophosphoryl)- dimethyl ether are obtained in the form of a yellowish oil. The compound corresponds to the following formula.

CHr-O O CH;

Analysis.C H O S P (molecular Weight: Calculated: 35.8% S. Found: 35.6% S.

EXAMPLE 2 Bis- (O O-z liethyl-dilhiophosphoryl) -dimethyl ether 165 grams of potassium diethyl dithiophosphate are suspended. in 250 cc. of methylene chloride and 38.5 grams of dichlorodimethyl ether are added dropwise in the course of /2 hour. The temperature of the mixture rises spontaneously to 45 C. After boiling the mixture under reflux for 2 hours it is filtered-to remove the residue of salt. By evaporating the solvent there are obtained 136 grams of pale yellow bis-(OzO-diethyl dithiophosphoryl)-dimethyl ether. The compound has the following analysis and formula.

Analysis.-C H O S P (molecular weight: 414). Calculated: 28.2% C, 5.80% H, 30.9 S, 15.0% P. Found: 28.6% C, 5.85% H, 30.8% S, 14.7% P.

CzHr-O O CzH EXAMPLE 3 Bis-(O O-dimethyl-dith iophosphoryl) -dimethyl sulphide EXAMPLE 4 Bis-( O O-diethyl-dithiophosphoryl) -dimethyl sulphide grams of potassium diethyl dithiophosphate, cc. of methylene chloride and 33 grams of dichlorodimethyl sulphide are heated at the boil for 4-5 hours. After being cooled, the organic solution is thoroughly agitated with water, then dried over sodium sulphate, and the methylene chloride is evaporated. 100 grams of slightly yellow bis (0:0 diethyl dithiophosphoryl)- OCHa OKs-0 OCHa 3 dimethyl sulphide remain behind. It has the following analysis and formula:

Analysis.C H O S P (molecular weight: Calculated: 37.4% S. Found: 37.1% S.

CaHy-Q P-S-CHz-S-OH2S-Ifi C2H5-0 S EXAMPLE 5 Bis-(O:O-diethyl-dithiophosphoryl) -1 :4-butylenedimethyl ether 02 15-0 O C2H5 0 CaHs EXAMPLE 6 Bis-(O O-diethyl-thiophosphoryl) -dimethyl sulphide 75 grams of the ammonium salt of OzO-diethyl-thiophosphoric acid are dissolved in 250 cc. of ethanol, and 27 grams of dichlorodimethyl sulphide are added. The mixture is boiled for 2 hours. After cooling the mixture, the precipitated ammonium chloride is filtered off with suction. The ethanol is evaporated from the filtrate and 73' grams of bis-(O:O-diethyl-thiophosphoryl)-di- 4 methyl sulphide remain behind in the form of an undistillable yellowish oil. It has the following analysis and formula.

Analysis.C H O S P (molecular weight: 398).

Calculated: 24.6% S, 15.9% P. Found: 23.8% S, 15.4% P.

C2HsO 00211 PSCH2SOH2-SP g\ 02135-0 OCzH EXAMPLE7 Bis-(0:O-diethyl-thiophosphoryl)-dimethyl ether 75 grams of the ammonium salt of OzO-diethyl-thiophosphoric acid are dissolved in 250 cc. of ethanol and 23 grams of dichlorodimethyl ether are added. The mixture is boiled, and, after being cooled, it is filtered. The ethanol is distilled from the filtrate, and grams of bis-(O:O-diethyl-thiophosphoryl)-dimethyl ether remain behind in the form of a colourless undistillable oil. It has the following analysis and formula:

Analysis.C H O S P (molecular weight: 382). Calculated: 16.8% P, 16.6% S. Found: 16.3% P, 16.7% S.

Bis-(OzO-diethyl dithiophosphoryl) 1:4 butylenedimethyl ether.

References Cited in the file of this patent FOREIGN PATENTS 515,666 Canada Aug. 16, 1955 

